Some embodiments of the present disclosure may relate to a control voltage adjusting circuit, a feedback signal generating circuit, and a control circuit including the same.
In existing liquid crystal display (LCD) devices, cold cathode fluorescent lamps (CCFLs) have mainly been used as backlight light sources. However, light emitting diodes (LEDs) have gradually been introduced as light sources in backlight units, due to various advantages, such as low power consumption, a relatively long lifespan, environmentally-friendly characteristics, and the like.
In order to drive the LEDs, a power supply circuit for converting alternating current (AC) power into direct current (DC) power and a driving circuit for controlling the supply of the DC power to the LEDs may be generally used.
The driving circuit for the LEDs may control the supply of the DC power so that an output current supplied to the LED is linearly varied in proportional to a dimming voltage input from an external voltage source. Recently, it has been necessary to uniformly maintain a level of the output current at a dimming voltage threshold level or less.